As the spring mount at the top of the shock absorber assembly, the top mount absorbs more than a quarter of the vehicle’s weight in impact forces when driving on uneven roads, playing an indispensable role. Today, let’s take a closer look at it!

The function of the top layer

The shock absorber top mount is made of rubber and serves to cushion and dampen vibrations. When the spring is fully compressed, the vehicle body is subjected to a significant impact transmitted from the wheels; without the cushioning provided by the shock absorber top mount, this intense impact would not only damage the shock absorber but could also cause the wheel hub to deform.

The top rubber on shock absorbers also provides sound insulation. When tyre noise is generated by contact with the road surface, the top rubber helps to dampen this noise, preventing excessive noise from being transmitted into the cabin; furthermore, it reduces the direct impact on the vehicle body when the tyres encounter bumps on uneven surfaces.

It is precisely thanks to the shock-absorbing top rubber that we need not worry about the car sustaining damage from severe vibrations when driving on bumpy roads. When the tyres hit a dip, the shock-absorbing top rubber also helps to keep the body of the car stable.

Top-to-bottom clearance

There is often a gap between the shock absorber top mount and the retaining ring; the exact size of this gap varies depending on the vehicle model and design specifications. This gap is intentionally incorporated to enhance damping performance. Under normal circumstances, a gap of less than 20 mm in the front shock absorber top mount is considered normal. However, this figure varies from vehicle to vehicle, and specific details should be checked against the vehicle’s technical specifications.

However, if the gap is too large or too small, this may adversely affect the vehicle’s handling and safety.

To be more specific, excessive clearance may cause abnormal noises. Conversely, insufficient clearance may result in the shock absorbers becoming too stiff, which will also detract from the driving experience.

The cause of excessive or insufficient clearance between the top rubber and the shock absorber is the ageing or damage of the top rubber.

Signs of damage to the top layer

Ride comfort is reduced, and unusual noises may be particularly noticeable when driving over bumps or speed bumps; this is a warning sign that there is a problem with the suspension system.

Tyre noise increases, and in severe cases, a rumbling sound can even be heard.

The vehicle veers off course; even when driving in a straight line, the steering wheel may pull to one side, and the vehicle may still be unable to maintain a straight course after correction.

When turning the steering wheel whilst stationary, a squeaking noise may be heard; in severe cases, this may even cause the vehicle to pull to one side whilst driving.

If any of the above symptoms occur, you should immediately have the vehicle inspected by a professional or have the parts replaced as necessary. It is worth noting that there is no fixed schedule for replacing shock absorber top mounts; instead, this should be done as soon as any issues are detected, based on the actual condition of the vehicle, to ensure driving comfort and safety.

Tips for Extending the Life of Your Top Sheet

The worst thing you can do to the top mounts is to drive over speed bumps and rumble strips at high speed. As long as you slow down—reducing your speed before you reach the speed bumps or rumble strips, rather than braking as you go over them—this will benefit the shock absorbers, top mounts, engine mounts and indeed all the rubber cushioning components on the chassis.

• Contact Us for Vehicle-Specific Bushings: natasha@nafurancar.com

As a key component of a car’s chassis, the shock absorber serves to dampen the vibrations caused by the spring rebounding after absorbing shocks and to absorb the energy from road impacts. However, as friction between the components leads to rapid wear and tear, this is where its trusty companion, the ‘top rubber’, comes into its own.

The top mount, acting as the spring seat at the top of the shock absorber assembly, absorbs impacts equivalent to more than a quarter of the vehicle’s weight whilst driving on uneven roads; its role is indispensable. Today, let’s talk about it!

A shock-absorbing top rubber is essentially a pressure top rubber; in layman’s terms, it is also known as a shock-absorbing frame bearing.

The function of shock-absorbing top rubber

The shock absorber top mount is made of rubber and serves to cushion and absorb vibrations. When the spring is fully compressed, the vehicle body is subjected to a relatively strong impact transmitted from the wheels; without the cushioning provided by the shock absorber top mount, this intense impact would not only damage the shock absorber but could also cause the wheel hub to deform.

The top rubber on shock absorbers also provides sound insulation. When tyre noise is generated by contact with the road surface, the top rubber helps to reduce this noise, preventing excessive tyre noise from being transmitted into the cabin; it also reduces the direct impact on the vehicle body when the tyres encounter bumps on uneven road surfaces.

With shock-absorbing rubber, we need not worry about the car sustaining damage from severe vibrations when driving on bumpy roads. The purpose of the shock-absorbing rubber is to keep the body of the car stable even when the tyres sink into the road, making for a more comfortable driving experience.

Situations in which the top rubber needs replacing

Among the common causes of damage to car shock absorbers, in addition to the shock absorbers themselves, damage to the shock absorber top mounts is also a factor. Generally speaking, there is no need to replace the shock absorber top mounts on a regular basis, unless any of the following situations arise:

1. Abnormal noises: When the shock absorber top mount is damaged due to severe wear, the vehicle’s shock absorbers will emit abnormal noises whilst in operation.
2. Steering Deviation: When the shock absorber top rubber seal is damaged, the vehicle may exhibit slight steering deviation, difficulty in returning to the straight-ahead position, and reduced steering effort.
3. Increased noise: Without the cushioning provided by the top mount, the shock absorbers transmit all the vibrations and impacts they absorb directly from the chassis to the passenger compartment whilst in operation.
4. Noise when turning on the spot: Even if the shock absorbers are not functioning, excessive wear and damage to the top rubber bushings can cause a very distinct noise when the steering wheel is turned whilst the vehicle is stationary.
   

How can I extend the service life of the top coat?

In everyday urban driving, the biggest cause of wear to the top rubber bushings is probably driving over speed bumps and vibration-damping strips at high speed. As long as you slow down before reaching them—rather than driving over them with your foot on the brake—this will benefit the shock absorbers, top rubber bushings, engine mount bushings and indeed all the rubber cushioning components on the chassis.

Nafurancar top mounts are all made from high-quality rubber using OE manufacturing processes, offering superior cushioning performance and ensuring a smoother, more comfortable ride for your vehicle.https://www.nafurancar.com/shock-absorber-strut-mount_c3